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प्रश्न
Use Einstein's photoelectric equation to explain the observations from this graph ?
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उत्तर
The Einstein's photoelectric equation is \[K_{max} = \frac{1}{2}m \nu^2_{max} = h\nu - \phi_o\]
From the graph, we noticed that
(i) The value of stopping potential is different for radiation of different frequencies.
\[\text { As } \]
\[e V_o = h\nu - \phi_o \]
\[\text { Hence }, V_o \propto \nu\]
(ii) The value of stopping potential is more negative for radiation of higher incident frequency.
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संबंधित प्रश्न
Draw a neat labelled circuit diagram of experimental arrangement for study of photoelectric effect.
The photoelectric work function for a metal is 4.2 eV. If the stopping potential is 3V, find the threshold wavelength and maximum kinetic energy of emitted electrons.
(Velocity of light in air = 3 x 108m/s,
Planck's constant = 6·63 x10-34 J -s,
Charg.e ori electron = 1·6 x 10 -19 C)
In an experiment of the photoelectric effect, the graph of maximum kinetic energy EK of the emitted photoelectrons versus the frequency v of the incident light is a straight line AB shown in Figure 6 below:
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1) Threshold frequency of the metal
2) The work function of the metal.
3) Stopping potential for the photoelectrons emitted by the light of frequency `v = 30 xx 10^14 Hz`
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On what factors does the number of emitted photoelectrons depend?
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Plot a labelled graph of IVsl where Vs is stopping potential versus frequency f of the incident radiation.
If the frequency of the incident radiation is increased from 4 × 1015 Hz to 8 × 1015 Hz, by how much will the stopping potential for a given photosensitive surface go up?
Light of wavelength 4000 Å is incident on two metals A and B. Which metal will emit photoelectrons, if their work functions are 3.8 e V and 1.6 e V respectively?
The phenomenon of photoelectric emission was observed by ______.
Consider an electron in front of metallic surface at a distance d (treated as an infinite plane surface). Assume the force of attraction by the plate is given as `1/4 q^2/(4πε_0d^2)`. Calculate work in taking the charge to an infinite distance from the plate. Taking d = 0.1 nm, find the work done in electron volts. [Such a force law is not valid for d < 0.1nm].
